IMPACT 3
| Type | Oceanographic cruise |
|---|---|
| Set | This cruise is part of the set IMPACT : IMPACT PHYSIQUE DES ENGINS DE PÊCHE |
| Ship | Thalia |
| Ship owner | Ifremer |
| Dates | 15/10/2000 - 19/10/2000 |
| Chief scientist(s) | VINCENT Benoît  |
LABORATOIRE TECHNOLOGIE BIOLOGIE HALIEUTIQUE 8 rue François Toullec 56100 Lorient +33(0)2 97 87 38 00 |
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| DOI | 10.17600/70140 |
| Objective | This cruise is part of the CPER 2000-2006 "physical impact on fishing gear on seabeds" programme. The approach used in the impact study was to perfect experimental methods at sea to study the impact of fishing gear on the bottom (impact on the benthos and physical effects) and develop a numerical model to predict impacts. We were interested in the main parts of fishing gear that could impact seabeds (trawl doors, ground rope, cables and chains). The aim is to describe the populations on three different sedimentary zones (mud, find sand, gravel) in the Bay of Biscay which are used for bottom trawling fisheries. 3 stations per zone were sampled. At each station, 5 Hamon grab, 1 beam trawl and 5 core samples were performed: the Hamon grab was used to characterize the populations in terms of species richness, abundance and biomass (0.25 m2 of surface sampled, vacuum sieving on 1 mm mesh), the beam trawl (10 mm mesh) to characterize more widely distributed species, species that are probably more 'sensitive' to trawling and the corer to define the sedimentary characteristics (granulometry, organic matter) and the vertical distribution of the fauna. Select zones: For the "Grande Vasière" mudflat (50 nautical miles southwest of Belle-Île): 46°58'N- 3°45'W; 46°58'N - 3°24'W - 46°52'N -3°36'W; 46°52'N-3°28'W / West of Birvideaux, "Bank Grek": 47°30'N-3°27'W; 47°30'N-3°24'W -47°28'N - 3°27'W; 47°29'N - 3°24'W / West of the Brittany point: 48°10'N - 4°55'W; 48°10'N - 4°53'W - 48°05'N - 5°00'W; 48°06'N - 4°51'W. |